Apparatus for producing oscillographic records



Jan. 30, 1951 c. M. HATHAWAY 2,539,832

APPARATUS FOR PRODUCING OSCILLOGRAPHIC RECORDS Filed Oct. 26, 1942 2Sheets-Sheet l flail/6 28 MHaZ /zaweg C. M. HATHAWAY APPARATUS FORPRODUCING OSCILLOGRAPHIC RECORDS Jan. 30, 1951 Filed Oct. 26, 1942 2Sheets-Sheet 2 AJ/3073A ww mm S3 CZazzde Patented Jan. 30, 1951APPARATUS FOR PRODUCING OSCILLOGRAPHIC RECORDS Claude M. Hathaway,Denver, 0010.

Application October 26, 1942, Serial No. 463,380

13 Claims.

My invention relates to oscillographs or recording systems and anapparatus for producing an oscillographic record.

Frequently, it is desired to provide an oscillograph which is designedfor automatically recording chance or unanticipated transients anddisturbances. In providing any arrangement suitable for this purpose, itis desired to maintain the oscillograph in a substantially de-energizedcondition during all periods when no transients or disturbances areoccurring. To maintain the oscillograph de-energized for such periodsrequires some arrangement whereby fullspeed recording of theoscillograph may be obtained within a relatively short time intervalafter the beginning of a transient or disturbance. Since oscillographrecording mechanisms are usually provided with a motor driving means anda roll of record paper or film it will readily be appreciated that theseelements have a certain amount of inertia which must be overcome beforefull speed operation thereof is obtainable. Since however, a record isdesired shortly after the beginning of a disturbance or fault, othermeans must be provided which will provide for such a record during thetime that the inertia of the elements is being overcome and thereafterwhen full speed of the normal recording elements is obtained, theinitial recordin apparatus may be permitted to become inactive.Therefore in accordance with the present invention, means are providedwhich are responsive to an abnormal condition or disturbance to initiatethe normal recording apparatus of an oscillograph and also to start intooperation an auxiliary apparatus for making a record during the earlyportion of the operating period immediately following such disturbances.This is accomplished by providing a device having a relatively highinitial energy value so as to rapidly place into motion certain otherdevices and thereafter the operation of the auxiliary apparatus isgradually reduced until the acceleration of the regular recordingapparatus has brought it to its normal operating speed.

Therefore it is an object of my invention to provide an improvedoscillograph arrangement which will automatically record chance andunanticipated transients and disturbances.

Another object of my invention is to provide in an automaticoscillograph an auxiliary record driving mechanism operated by meanshaving a high initial energy value.

Another object of my invention is to provide in an automaticoscillograph a high energy record driving mechanism which is operativeduring the initial stages of recordation during the period when thenormal recording apparatus is accelerating to its normal operatingspeed.

Still another object of my invention is to provide a record drivingmechanism in anoscillograph which utilizes stored mechanical energywhich is released in response to the occurrence of a transient, fault ordisturbance.

Still another object of my invention is to provide a recording apparatusfor an oscillograph which upon the occurrence of a transient ordisturbance will within a relatively brief time interval move the recordreceivin medium at substantially the normal operating speed thereof.

A further object of my invention is to provide an improved apparatus forproducing an oscillographic record which will operate for apredetermined time interval after the occurrence of a disturbance ortransient. A

Still another object of my invention is to provide an improved apparatusfor obtaining a record which after a predetermined time interval willstore energy in a mechanism for use during the initial period of thenext recording interval.

' A still further object of my invention is to provide in an automaticoscillograph an improved arrangement for rendering the oscillographinoperative during the period in which the mechanism thereof is beingreset for recording a successive transient.

Other and further objects of my invention will become more readilyapparent by reference to the following specification taken in connectionwith the accompanying drawings wherein Figure 1 is a circuit diagram ofthe electrical apparatus controlling the automatic operation of anoscillograph; Figure 2 is a schematic representation of variousmechanical elements provided for making a record; and Figure 3 is acurve illustrating certain operating characteristics of various elementscomprising an oscillograph constructed in accordance with my invention.

Referring more particularly to Figure 1, there is shown a pair ofterminals ll connected to a suitable source of power. Connected acrossthe source of power is a series of pairs of contacts l2, l3 and M whichare connected in series with three relays in parallel, one having a coilI5, another having a coil l6, and the other having a coil 20. a

The relays I6 and 29 are arranged normally to hold thereagainstarmatures 21 and 3!! respectively, the purpose of which will become morereadily apparent in the description given in connection with Figure 2.The pairs of contacts l2, l3 and M are each controlled by one of aplurality of armatures H, l8 and I9 which are arranged opposite aplurality of magnetic relay cores 2|,

voltage relay having an armature H which is held in the position shownby the energy flowing through the coil 24. When the voltage across thecoil 24 decreases below a predetermined amount,

the armature I! will drop because of a decrease in the magnetic flux ofthe relay 24 and the fact that the armature is sprin biased to open thecontacts 62. The relays 22 and 23 each have a soft iron core providedwith a coil so that when an over-voltage condition or an over-currentcondition occurs the relay will attract its armature. In order toprovide high speed operation in response to transient conditions thearmatures i8 and 59 are normally held downward by the attraction ofpermanent magnets 9 and i8 thereby holding the contacts is and i l inclosed circuit relation. When the attraction of the upper magnet exceedsthat of the permanent magnet, the armature is pulled upwardly away fromthe permanent magnet. Each of the armatures is also spring biased towardthis upward position. The permanent magnet normally has suincientstrength to retain the armature in closed circuit position until theelectromagnet is energized. Whenever an electromagnet is energized, thearmature is pulled away from a permanent magnet and thus the attractionof the permanent magnet is greatly decreased thus resultin in a highlyeffective force for moving the armature. The armature once having beenattracted away from the permanent magnet is retained in its position bya suitable spring bias.

Thus if any one of the relays 2!, 22 or is actuated in response to theoccurrence of a condition which it is desired to be recorded, thearmature thereof will be moved to op n the contacts controlled thereby.Thus actuation of one of these relays will cause the opening of one ofthe pairs of contacts i2, E3 or it. When any one of these pairs ofcontacts are opened, the relay coils i5, i and 29 will becomede-energized The r lay !5 is provided with stationary contacts 2E3, and341 and with cooperating movabl contacts 29, 32 and 33. There is alsoprovided a resetting mechanism for the armatui ii to 59 comprising aplurality of levers and 3? which are connected to the core of a solenoid353, one side of which is connected to one terminal i i of the source ofpower and the other side of which is connected to a contact 39'ar=ranged to cooperate with a contac't' i-l which in turn is connected tothe other terminal i i of the source of power. The contacts 33 and iiare normally open circuit and are arranged to be closed for a short timeinterval by a cam which is driven by a motor 63. The motor by drivingthe cam 52 also operates a switch having contacts to is inclu ive, soarranged that when actuated, first the contacts l 'i and 25 are closed,then the contacts Q5 and ll and thereafter the contacts 48 and 39 areopened from their normally closed circuit relation.

i'here is also provided a plurality of relays having coils 5i, 52and 53.The relay El is pro vided with two movable contacts '53 and 55 which arenormally in open circuit relation with resnect to stationary cooperatingcontacts 56 and The relay 52 is provided with a movable contact which isnormally in closed circuit relation with a contact 59 but which may hemoved therefrom to closed circuit relation with contact G5. The relay 53is provided with two movable contacts 62 and 63 which are arranged to bemoved to closed circuit relation with stationary contacts 6 3 and 65.There is also provided a motor 68 which drives a cam switch 6! arrangedto close for a short interval a pair of contacts 68 and E59 andthereafter to open a pair of normally closed contacts ii and 32. Ashutter closing solenoid i3 is connected between the contact 3 1 of therelay coil 55 and the contact ll of the switch operated by the cam 32.

The contact 28 of the relay i5 is connected to one terminal of the relay5! and also to the contact GS of the switch operated by the cam 52 whichin turn is connected to the contact 32 of the re lay H5. The contact 29which cooperates with the contact 28 is connected to one side of thesource of power. The contact 32 which cooperates with the contact 3i isconnected to the contact id of the cam switch 42 and also to the contact56 of the relay 5E. The contact M of the cam switch 62 is connected tothe contact 5'! of the relay 5!, one side of the relay 52 and also toone side of the motor 63. The other side of the relay 52 and the otherside of the motor 43 are connected to the return wire of the powersource H. The contacts 45 and 45 of the cam switch 52 and the contacts 55 and 55 of the relay 55 are connected to the upper side of the sourceof power H. The contact 58 of the relay 52 is connected to the upperside of the source of power 5 i. The contact 59 which normally engagesthe contact 53 is connected to the contact 83 of the relay 5-3 and alsoto the contact 69 of the switch operated by the cam iii. The contact 6!of the relay 52 is connected to one side of the relay 53 and also to thecontact ii of the switch operated by the cam 5?. The other side of therelay 53 is connected to the other terminal of the power source H. Thecontact ii of the cam switch Ell is connected to the contact 6 of therelay 53. connected to the contact 63 of the cam switch 5'! and al o toone side of the motor 55.

Connected in parallel with the pairs of contacts i2, i3 and M which arecontrolled by the armatures ill, 98 and i9 of the relays 2Q, 25 and 26respectively, are a pair of contacts and (it! which normally are in opencircuit relation. The contact 59 is mounted on or actuated by a leveriii which is spring biased by a spring ii} towards closed position. Thelever Till is arranged to onerate in response to exhaustion of thesupplyof record receiving material in a record magazine thereby torender inoperativethe entire apparatus when the record receivingmaterial has been exhausted. The purpose and operation of thisarrangement will become more readily apparent in the description of theoperation of the ap paratus.

Referring now to the schematic showing of Figure 2 of the drawing, thereisprovided a source of light M which is directed upon the movableelements of a plurality of galvanometers one of which is indicated bythe rectangle from which the light is reflected towards alens it whichdirects the light towards a record mate? rial or film ll whenever ashutter '58 is not interf, posed infront-of the-lens 7-6; Aplurality-of-gal The contact 65 of the relay 53 is vanometers arearranged in a row extending in back of the first galvanometerrepresented by the rectangle 15. The shutter 18 is actuated by a lever-'|9 which is spring biased by a spring 8| in a direction tending tomove the shutter out of the path of the light between the galvanometerl5 and the lens '56. The lever 19 is latched by one end of an armature39 which is retained in that position by the magnetic flux of the coreby the normally energized relay 29. When the coil surrounding the coreof the relay 2?] is de-energized, the armature is released therebydisengaging the lever 18 so as to move the shutter 18 out of the lightpath. After the recording apparatus has operated for a predeterminedperiod of time, the coil is again energized and a solenoid i3 isenergized so that a rod operated thereby engages one end of the lever'19 which again moves the shutter 18 into the path of the light andlatches the shutter into this position by engaging armature 30 of therelay 20. The relay I6 which is provided with an armature 2'! retains inlatched position a lever 82 until the coil I6 is deenergized. The lever82 is retained in latched position against the action of the bias of atenwhich extends through an aperture 86 formed adjacent one end of aconnecting rod 8'1. At a point adiacent the other end of the lever 82,there is a dash pot 88 which serves to retard the motion of the lever 82after the lever has moved a predetermined distance upon being releasedby disengagement of the lever 82 from the armature 21. The particularfunction and operation of the dash pot 88 with respect to the lever 82will subsequently become more readily apparent in the explanation of theoperation of the oscillograph a paratus at which time reference willalso be made to Figure 3.

The other extremity of the connecting rod 57 is connected to a crank orcam member 89 when in turn is driven by the motor 66. The crank 89 isalso connected to a link 9|, one extremity of which is pivotallyconnected to an intermediate portion of a lever 93. At the free end ofthe lever 93, there is positioned a roller 94 which is arranged toengage at certain times, the record paper or film TI. The recordingapparatus includes a supply magazine 95 from which the record receivingmaterial T1 is supplied, and after the record has been made, the recordreceiving material is taken up in a receiving magazine 96. Interposedbetween the supply magazine 95 and the receiving magazine 95 are threeidler rollers 91 to 99. The motor 43 is connected by means of a springbiased friction clutch lilll to the record receiving roll within thereceiving magazine 96. The motor 43 also is connected to one of a pairof rolls HM and I222 which normally, when the motor 43 is operating atfull speed, operate to move the record receiving material or papertherebetween at a predetermined relatively constant rate The initialpositions of the roller 84 and the roller 94 are shown in solid lines,and the subsequent positions are indicated by the dotted lines. In thesolid line position illustrated, the mechanism is in readiness torespond to the detection of a transient or disturbance by one of therelays 24 to 29 of Figure 1 whereupon the relays l5 and 20 will bede-energized thereby permitting the roller 84 to move to its secondpositiong After the recording apparatus has ill) been recording for acertain time interval, the motor 66 will become energized thus movingthe crank 89 to position the roller 94 at its second position whichbrings about the formation of a loop of record receiving material atI03. The record receiving paper may therefore be traced from the supplymagazine to the idler roller 97, past the roller 94 of the lever 93,thence to the idler roller 98, over roller 99, the roller 84 of thelever 82, between the rollers |0| and I92, and then into the receivingmagazine 96. The roller 99 is positioned beneath the lens 16 so that therecord on the paper is made when the paper passes over this roller 99.

The record magazine 95 is provided with a lever mechanism indicated bythe lever 19 which is arranged to be responsive to the depletion of therecord receiving paper or material in the magazine 95. When the recordreceiving material in the magazine 95 has been exhausted, the levermechanism represented by the lever 16 will be permitted to operate sincethis mechanism is biased by a suitable spring 40 so arranged as to tendto close the contacts 5|! and 6! Therefore when the record receivingmaterial magazine is empty, the contacts 59 and 69 are closed, therebypreventing de-energization of the relays I5, l6 and 29 and hence theentire recording apparatus is maintained in an inoperative condition.

Reference may now be had to Figures 1 and 2 in connection with thefollowing explanation of the sequence of operations occurring in a cycleof operation of the apparatus. It will be assumed that one of the relays24 to 26 has been actuated in response to a fault, a transient or adisturbance. Thus the armature of one of these relays is actuated sothat one of the pairs of contacts l2, I3 or H! is opened therebyde-energizing'the relays l5, I6 and 29. The de-energization of the relay20 permits the shutter 18 to snap open so that light from the source I4impinging on the galvanometers 15 may pass through the lens 16 to thepaper I! immedately above the roller 99. The de-energization of therelay l5 releases the armature 2! from engagement with the lever 82 sothat the tension spring 83 moves the roller 84 toward the left. Thelever 82 is permitted a certain amount of relatively free movementbefore the collar I23 on the end of the piston rod of the dash pct 88 isengaged. The de-energization of the relay l5 permits the closing of therelay contacts 28, 29; 3|, 32; and the opening of contacts 33, 3Q. Theclosing of the contacts 28, 29 energizes the relay 5| so that itscontacts 54., 55 and 55, 51 are closed. The closing of the contacts 54,55 looks in the relay 5| since this brings about a short circuiting ofthe contacts 28, 29 of the relay IS. The relay 5| can now only beopened. at a subsequent time by the opening of the contacts 48, 49 ofthe cam switch 42 which are in series with the locking circuit. Thecontacts 55 and 51 of the relay 5| when closed bring about theenergization of the motor 43 which drives the cam 42, the drivingrollers NH and H32, and the takeu reel within the receiving magazine 96.The motor 43 thereupon accelerates until its normal operating speed hasbeen attained.

The closing of the contacts 55 and 51 of the relay 5! also causesenergisation of the relay 52 so that its contacts 58 and 59 areseparated and contacts 58'and 5| areclosed. The closing of the contacts58 and 6| of the relay 52 energizes the relay 53 thereby closing thecontacts 63, 55 and B2, 64. The closing of the contacts 52, fi lshortthe relay 53 will not open when these contacts are again opened. Afterthe relay 53 has been locked in by the closing of the contacts 52, 54,the relay cannot be opened until the contacts 1 I, 12 of the cam switchBl are interrupted since these contacts are connected between thecontacts 52, 64 and the relay coil of the relay 53. The contacts 63, 65of the relay 53 are in circuit with the motor 56 which however isprevented from running since it is connected through the open contacts58, 59 of the relay 52 to one side of the power source H. The resettingmotor 65 therefore cannot start until the relay 52 is deenergizedthereby permitting the closing of the contacts 58, 59. I v

' When the chart driving motor 43 is started by the operation of therelay which closes the contacts 55, 51, the cam 42 begins to rotate in aclockwise manner. After about three-fourths of a revolution, thecontacts (it, 4% are closed which energizes the solenoid 38, so as tooperate the levers 95 to 971' to reset the armatures ll to H9 of thestarting relays 24 to 25. If at that time there is no longer anydisturbance affecting any of these relays, the armatures thereof willremain reset so that the relays or electromagnets it and 26, areenergized and the reTay l5 will have opened its contacts. The motor 43and the cam 42 will continue to run because the relay Si is locked in.As the cam 42 continues to rotate, the contacts 44 and 45 which are inparallel with contacts 55, 51 of relay 5i will first be closed. Theclosng of the contacts 46 and 41 energizes the shutter closing solenoidE3 to move the shutter in front of the lens. The next contacts to beactuated by the cam 42 are cont-acts 43 and 49 which are thereuponseparated. These contacts are in the holding circuit for the relay 5!which when deenergized, opens the contacts 55 and 5'? of the motor 53.The motor 43 however continues to run because the closed contacts and 45are in parallel with the contacts 55 and 51. The cam therefore continuesto move until the contacts 44 and 45 are opened. When these contacts areopened, the shutter closing solenoid E3, the motor 43 and the relay 52are all de-energized. When the relay 52 is deenergized, the contact 58strikes the contact 59 thereby setting into operation the resettingmotor 66 which drives the crank 89. The crank 89 moves the connectingrod 81 so thatthe lever 82 is locked into position by the armature 27 ofthe electromagnet It. The roller 94 is moved from its solid lineposition to its dotted line position thereby establishing a new freeloop of paper i935. The crank continues to rot-ate to return the rol er94 to its solid line position. The resetting motor 55 thereupon isde-energized by the operation of the cam 67 which closes the contacts58, 59 and opens contacts ii and '52. The opening of the contacts H andi2 tie-energizes the relay 53 thereby opening the contacts 53, 65. Thishoweverdoes not stop the resetting motor 66 because these contacts areshort cirouited by the contacts 68, 59. The cam 6? rotates thensufficiently until the contacts 63, as open thereby stopping theresetting motor as after one revolutionof the cam 51. The oscillographapparatus therefore has beenreturned to its original condition and isnow ready fo another cycle of operation. I If at the time that the chartmotor 49 was driving the cam 42 to the position where the'contacts 4iand 35 were engaged, there stll has been a disturbance on any one of therelays 24 to 26, one of these relays would not have remained reset-edthat one -01- the pair's-pf contacts lZ to I4 would again have opened.This would have brought about a closing of the contacts 28, 29 and (H,32 of the relay 15 as soon as the contacts 39, 4| of the cam switch hadopened. Since the contacts 3!, S2 of the relay i5 are across thecontacts 48, 49 of the cam switch 42, the relay 5| would not have beenopened when the stud on the cam 42 operated these latter contacts.Therefore, the chart motor 43 would have continued to drive the cam 42for another revolution. Therefore, the oscillograph would continue inoperation until all of the starting relays 24 to 26 have their armaturesll to E9 reset so as to close the pairs of contacts I2 to [4.

If at the time that the resetting solenoid 38 had closed all of thearmatures I? to I9 of the starting relays 24 to 26, and the resettingmotor 66 has started operating, a subsequent actuation of any one of thestarting relays will not start the oscillograph until the resettingoperation has been completed. This is brought about by the fact that arelay til is connected in parallel with the motor 65 and its contacts 99are in parallel with the pairs of contacts 52 to i l of the startingrelays and the electromagnets l6 and 28. This makes it impossible totie-energize the relay l5 as long as potential is being supplied to theresetting motor 66 and hence no cycle of operation can be initiatedunless the relay i5 is de-energized.

In the previous description of the operation, it will be remembered thatde-energization of the electromagnet it permits the armature 2'? tounlatch the lever 82 which was permitted a certain free movement beforeengaging the dash pot 88. By referring to Figure 3, it will be seen thatthere has been plotted velocity against time. The curve represents theoperation of the roller 84. The roller therefore during a small timeinterval I06 which maybe in the vicinity of one twohundred-fortieth of asecond permits relatively rapid acceleration of ths roller until themaximum is reached whereupon the dash pot 88 becomeseifective.Thereafter, there is a deceleration along the curve as shown. Over theperiod of the curve E95, the chart motor 43 is accelerated and thisacceleration curve may approximate the curve such as it? so that it maybe seen that shortly after the time interval I65, the resultant velocityof the paper 'll across the roller 99 is a relatively constant quantity,This action takes place because the driving rollers Illl and H02 areaccelerated until the normal operation thereof is obtained. The normaloperation of the rollers HM and sea is reached at about the time thatthe roller 84 has reached the limit of its travel. The receivingmagazine roller of the magazine 93 is driven through a friction clutchwhich tends to drive it faster than necessary so as to keep the papertightly wound on the reroll spool. The paper passing through the rollersIUI and W2 however, if the normal speed of these rollers has beenattained, is at a constant rate regardless of the amount of paper in thesupply magazine or in the receiving magazine. From the abovedescription, it will be seen that when the oscillograph is not recordingthere are no parts in motion and only the oscillograph lamp l4 isenergized in addition to the relays 55, I 5 and 29. From Figure 3, itwill be seen that full speed operation of the record obtained within arela tively short time interval such as approximately onetwo-'hundred-fortieth of a second after a transient condition has begun.

Since an automatic apparatus has been provided for recording thecurrents of transients cit-unanticipated con'ditionsit willheappreciatedthat it is desired to reduce the operation of the oscillograph to aminimum. In addition to plyof record material or paper in the supplymagazine 95 has been exhausted. This is ac- .complished by providing asuitable lever means indicated by the lever 10 which is biased by aspring 48 so as to tend to close a pair of contacts 50 and 69. When therecord material has been used up, the contacts and 60 will be closed.Since the contacts 59 and 60 are in parallel with the contacts l2, l3and 14 of the relays 24 to 25, it will be appreciated that any transientoccuring which may open any of the contacts 12 to Hi cannot initiate theoperation of the oscillographic apparatus since the opening of one ormore of such contacts cannot deenergize the relays l5, l6 and 20.Therefore, the oscillogranh is maintained in an inoperative conditionuntil a new supply of record material is provided for the magazine 95.

While for the purposes of illustrating and de" scribing my invention, aparticular embodiment has been employed, it is to be understood that Iam not to be limited thereby since obviously modifications may be madein the circuit arrangements and in the mechanical instrumentalitiesemployed without departing from the spirit and scope of my invention asset forth in the appended claims.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. In an oscillographic recor ing apparatus, the combination comprisinga source of light, a galvanometer, means for directing light from saidgalvanometer to a recording point, a normally closed shutter interposedbetween said galvanometer and said recording point, mechani cal meansbiasing said shutter toward an open position, electromagnetic means forretaining said shutter in closed position, and means responsive to aphenomenon to be recorded for de-energizing said electromagnetic meansretaining said shutter in closed position.

2. In an oscillographic recording apparatus,

the combination comprising means responsive to an occurrence of acondition to be recorded for initiating the operation of said recordingapparatus for a predetermined time interval, means for moving a recordreceiving medium past a recording pointand an auxiliary record receivingmedium moving means arranged to be operative during-the period in whichsaid first means accelerates to its normal operating speed, saidauxiliary means including mechanical energy storage means adapted tomove with high initial velocity and being arranged to be released uponoccurrence of said condition to move said record receiving medium past arecording point at a velocity comparable to the normal velocity of therecord receiving medium as moved by said first means at its normaloperating speed, and means for gradually decreasing the velocity of saidauxiliary means during the period of acceleration of said firstmentioned record moving means.

3. In a recording apparatus, the combination comprising a source ofrecord receiving medium, a recording point, means responsive to the cocurrence of a condition to be recorded for producing a record on saidrecord receiving medium, normally inoperative means for moving saidrecord receiving medium past said recording point, means comprising atension spring and a lever arranged to move said record receiving mediumpast said recording point at a relatively high initial velocity uponoccurrence of a condition to be recorded, means responsive to theoccurrence of the condition for energizing said normally inoperativemeans, and a retarding means arranged to be energized by said leverafter movement over a predetermined distance, said retarding meansoperating ,to decelerate the movement of said lever whereby said recordreceiving medium will pass said recording point at a relatively uniformrate during the acceleration period of said normally inoperative meansfor moving said record receiving medium.

4. In an oscillograph for recording automatically the occurrence of acondition to be recorded including a record receiving medium movingmeans normally maintained in an inoperative condition, an energy storagemeans, an auxiliary receiving medium moving means arranged to beactuated by said energy storage means upon occurrence of said condition,means responsive to occurrence of said condition for rendering operativesaid record receiving medium moving means, and means correlating themovements of both said record receiving medium moving means so as tomove the record receiving medium past a recording point at a relativelyconstant rate of speed.

5. In a recording apparatus, the combination comprising a source ofrecord receiving medium, a recording point, normally inoperative meansfor moving said record receiving medium past said recording point, andmeans comprising a tension spring and a lever arranged to move saidrecord receiving medium past said recording point at a relatively highinitial velocity upon occurrence of a condition to be recorded, meansresponsive to the occurrence of said condition for energizing saidnormally inoperative means, and a retarding means arranged to be engagedby said lever after movement over a predetermined distance, saidretarding means operating to decelerate the movement of said lever,whereby said record receiving medium will pass said recording point at arelatively uniform rate during the acceleration period of said normallyinoperative means for moving said receiving medi- 6. In an automaticrecording oscillograph, having a plurality of galvanometer elements, the

combination of a plurality of relays each arranged to be responsive to adifferent condition to be recorded, a plurality of serially connectedcontacts each arranged to be interrupted by the action of one of saidrelays, a recording point, a light source for said galvanometerelements, means directing light therefrom to said recording point, ashutter retained in closed position adjacent said recording point byelectromagnetic means connected in series with said contacts, saidshutter being interposed in the path of said light, means controlled bysaid relays for opening said shutter, and means also connected in serieswith said contacts for controlling a cycle of operation of saidautomatic oscillograph.

7. The combination comprising a supply roll or" record paper, arecording point for making a record on said paper, means for forming aloop of paper of variable size between said roll and said recordingpoint, means for driving said record paper past said recording point,and auxiliary means between said recording point and said record paperdriving means for moving and increasin the size of saidloo of said paperpast driving .said record paper past said recording point at a constantrate, auxiliary means be-- tween saidfrecording pointand said drivingmeans for moving said paper past said recording point .during theacceleration periodof said first means, said auxiliary means includingmechanical energy storage means to actuate said auxiliary means for arelatively short time interval after .the initiationof operation of saidapparatus, and means operative at the end of a period of operation ofsaid apparatus for actuating said paper 1001?) forming means and forstoring energy in said mechanical energy storage means.

9. In an oscillographic recording apparatus, means for moving recordreceiving material for a predetermined time interval upon the occurrenceof a condition to be recorded, auxiliary record receiving materialmoving apparatus operative only during the acceleration period of theoperation of said first record receiving moving means, said auxiliaryapparatus including mechanical energy storage means arranged to bereleased upon occurrence of said condition to'actuate said apparatus andmeans subsequently operative at the end of the time interval ofoperation-of said first record receiving moving means for storing energyin said mechanism for use during the next --cycle of operation of saidrecording apparatus.

10. In an oscillographic recording apparatus having a recording cycleapparatus, said apparatus including electrical means for moving a stripof record receiving medium past a recording point and an auxiliarymechanical record receiving medium moving means arranged to be operativeduring the period in which said first means accelerates to its normaloperating speed,

electromagnetic means responsive to an occurrence of a condition to berecorded for initiating recording cycle apparatus for a predeterminedtime interval and initiating said auxiliary mechanical energy storagemeans efiective to move with high initial velocity and being arranged tobe released upon occurrence of said condition to move a loop of saidstrip of record receiving medium past said recording point at an initialvelocity comparable to the velocity of the record receiving medium asmoved by said first mentioned means at its normal operating speed.

11. In an oscillograph for recording automatically the occurrence of acondition to be recorded including a record receiving medium drivingmotor normally maintained in an inoperative condition, a mechanicalenergy storage means, an auxiliary record receiving medium moving meansarranged to be actuated by said mechanical energy storage means uponoccurrence of said condition, said auxiliary means being arranged tooperate for a relatively short time,

means responsive to occurrence of said condition for rendering operativesaid record receiving medium driving motor and said auxiliary means, andmeans correlating the movements of said "driving motor and saidauxiliary record receiving medium movin means so as to move the recordreceiving medium past a recording point at a relatively constant rate ofspeed while said driving motor attains normal speed.

212 112. In an .oscillographic recording apparatus, normally inoperativemeans for moving a record receiving :medium past a recording point :fora predetermined time interval .upon the occurrence of a condition to berecorded, .an auxiliary record receiving medium moving apparatusincluding an energy slorage mechanism, said auxiliary record receivingmedium moving apparatus being for subsequent actuation of said auxiliaryrecord receiving medium moving apparatus during the next cycle ofoperation of the recording apparatus.

13. In an automatic 'oscillograph for recording certain conditions, thecombination comprising an electrical record receiving medium movingmeans, an auxiliary mechanical record receiving medium moving means,mechanical energy storage means for actuating said auxiliary recordreceiving medium moving means, means responsive to the occurrence ofa-condltion to be recorded to energize said record receiving mediummoving means and to render operative said energy storage meansto actuatesaid auxiliary record receiving medium moving means, a recording point,means correlating the movements of both said record receiver movingmeans so as to move the record receiving medium at a relatively constantrate past said recording point during the acceleration period of saidfirst means, and electrical means operable subsequent'to the operationof said first record receiving medium moving means for storing energy insaid mechanical energy storage means for subsequent use.

CLAUDE M. HATHAWAY.

REFERENCES CITED The following references are of record in the file ofthis patent;

UNITED STATES PATENTS Number Name Date 610,782 W-ich Sept. 13, 18981,017,984 Martin Feb. 20, 19 2 1,196,335 C-lokey Aug. 29, 1916 1,545,078I 1925 1,580,802 1926 1,684,309. 1928 1,779,324 1930 1,800,256 19311,817,432 Angus Aug. 4, 1931 1,871,379 Legg Aug. 9, 1932 1,883,907Hathaway 1- Oct. 25, 1932 1,853,960 Cunningham 1,... Apr. 12, 19321,919,697 Thompson July 25, 1933 2,034,543 Twiss et a1. Mar. 17, 19362,059,879 La Pierre Nov. 3, 1936 2,126,775 Hodgson Aug. 16, 19382,202,731 Crago May 28, 1940 2,256,746- Mayer Sent. 23, 1941 2,262,520Twiss Nov. 11, 1941 2,359,651 Krogh Oct. 3, 1944 2,467,008 Brown Apr.12, 1949

